Instruments of this type have been proposed for surgery in sites of the body that are difficult to make accessible. However, these instruments appear to have serious deficiencies preventing their use on rubbery and tough substances such as cartilage, hence many important surgical procedures have not been possible. Prior efforts in the field are represented, in the patent literature by U.S. Pat. Nos. 2,369,925; 3,618,611; 3,732,858 and 3,844,272 and in commerce by the interarticular shaver sold by Dyonics, Inc., corresponding to copending U.S. application Ser. No. 848,982 by Bonnell.